1. Field of the Invention
The present invention relates to an apparatus and method for positioning a probe head for use in a probe memory device.
2. Description of the Related Art
In general, a memory device of an HDD (Hard Disk Drive) system is known as a recording device mounted on an electronic device. A general recording medium of HDD system is formed in a disk shape, and is rotated at a high speed by means of equipment such as a spindle motor. A probe head section for carrying out recording and reproduction to this recording medium is provided at a tip end of a turning arm, and is opposed to a recording face. In the recording medium, specific patterns are disposed at predetermined intervals from the center in a radiation shape. At this pattern portion, feedback information (servo patterns) relating to a position for positioning the probe head section relative to the recording medium is described.
In addition, according to Japanese Patent No. 3105987, there is proposed an information recording and reproducing apparatus provided with: a recording medium fixed to a coarse movement mechanism; and a movable probe disposed in opposite to the recording medium. With respect to the recording medium, a smooth recording layer is provided on a glass substrate, and the recording medium is placed on an XY-direction coarse movement mechanism that coarsely operates in an xy-plane. An xy-direction fine movement mechanism and a z-direction fine movement mechanism are disposed in an overlapped manner above the recording medium, and one probe opposite to a recording face is provided on a lower face thereof.
In such a recording medium, in order to achieve an increase in amount of information to be recorded, it is preferable to carry out integration such that a recording density is enhanced. However, it is not easy to find out a technique for achieving a high density, and it is thought to merely increase an area of a recording face, thereby achieving integration. However, for a practical use, there is a need for increasing an information writing speed and readout speed. A movable range and a movement speed of one probe is limited, and thus, it is presumed to use a number of probes.
In the case where a number of such probes are disposed in a matrix shape, the plurality of probes having a probe column must face, at the same time or continuously, to a plurality of portions (extremely small recording area) at which the plurality of probes carry out recording/readout. Thus, positioning must be precisely carried out relative to an XY direction.
With respect to this positioning, in JP-A 9-26427(KOKAI), for example, there is proposed a positioning apparatus for carrying out relative position control between a probe and a stage. This positioning apparatus is provided at a scaling section formed in a saw-tooth shape having predetermined pitches all around a recording area (recording face) of a square shaped recording medium fixed on a stage, and a position detecting probe is made proximal thereto. The position detecting probe is fixed to a probe side substrate that moves in an XY direction by means of a laminate type piezoelectric actuator. This positioning apparatus detects a displacement by means of probes proximal to four scaling sections.
In general, as in the positioning apparatus of JP-A 9-26427(KOKAI) described previously, in the case where position detection in the XY direction is carried out, a pair of position identification patterns are provided, respectively, in two axis directions (XY directions) orthogonal to each other relative to the recording face. In other words, position identification patterns are provided all around the recording area. Conventionally, an approach for carrying out position detection at intervals has been also used in order to achieve time reduction of a position detecting process.
Further integration (downsizing) and an increase in recording area are required to increase a recording capacity of a square shaped recording medium that corresponds to a plurality of probe heads disposed in an arrayed manner described previously. In contrast, with respect to position detection in a Y direction, i.e., in a track direction, in particular, there is a need for carrying out continuous precise position detection while eliminating an undetected state.